Damped product with an insert having a layer including graphite thereon and methods of making and using the same

CROSS-REFERENCE TO RELATED APPLICATIONS

0001This application claims the benefit of the following priority applications: this application is a continuation-in-part of U.S. application Ser. No. 12/272,164, filed Nov. 17, 2008; and this application is a continuation-in-part of U.S. application Ser. No. 12/174,223 filed Jul. 16, 2008, which claims the benefit of U.S. Provisional Application No. 60/950, 906, filed Jul. 20, 2007.

TECHNICAL FIELD

0002The field to which the disclosure generally relates includes damped products including inserts and methods of making and using the same.

BACKGROUND

0003Products and certain components thereof may be subject to various vibrations and other oscillations when in use. Such vibrations could have undesirable effects such as, among other things, generating noise, having increasing frequency amplitude, or having a prolonged period of vibration modes.

0004Referring now to <figref idref="DRAWINGS">FIG. 1A</figref>, a prior art brake rotor <b>14</b>′ has been known to include a body portion <b>16</b>′ and an insert <b>18</b>′ received therein and having a layer or coating <b>28</b>′ thereon including ceramic or refractory materials. <figref idref="DRAWINGS">FIG. 1B</figref> is an enlarged view of a portion of <figref idref="DRAWINGS">FIG. 1A</figref>.

SUMMARY OF EXEMPLARY EMBODIMENTS OF THE INVENTION

0005One exemplary embodiment may include a product having a body portion, and a substrate such as, but not limited to, an insert. A layer including particles, such as graphite, is interposed between at least a portion of the substrate and the body portion, and wherein the substrate and the layer including the particles are constructed and arranged to damp vibrations of the body portion.

0006Other exemplary embodiments of the invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while disclosing exemplary embodiments of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

0007Exemplary embodiments of the invention will become more fully understood from the detailed description and the accompanying drawings, wherein:

0008<figref idref="DRAWINGS">FIG. 1A</figref> is a partial, sectional view of a portion of a vented brake rotor having a refractory coated insert embedded in a rotor cheek according to one prior art embodiment.

0009<figref idref="DRAWINGS">FIG. 1B</figref> is an enlarged view of a portion of the vented brake rotor illustrated in <figref idref="DRAWINGS">FIG. 1A</figref>.

0010<figref idref="DRAWINGS">FIG. 2A</figref> is a partial, sectional view of a vented brake rotor showing an insert with a layer including graphite embedded in one of the rotor cheeks according to one exemplary embodiment of the invention.

0011<figref idref="DRAWINGS">FIG. 2B</figref> is an enlarged view of a portion of a vented brake rotor illustrated in <figref idref="DRAWINGS">FIG. 2A</figref>.

0012<figref idref="DRAWINGS">FIG. 3</figref> is a sectional view of a brake rotor including a single rotor cheek having an insert with a layer including graphite thereon embedded in the rotor cheek according to one exemplary embodiment of the invention.

0013<figref idref="DRAWINGS">FIG. 4</figref> is a sectional view of a brake rotor including a single rotor cheek and including two inserts each having a layer including graphite thereon embedded in the single rotor cheek according to one exemplary embodiment of the invention.

0014<figref idref="DRAWINGS">FIG. 5A</figref> is a perspective view of a vented brake rotor including a first rotor cheek (outboard) and second rotor cheek (inboard), wherein each rotor cheek includes an insert having a layer including graphite thereon according to one exemplary embodiment of the invention.

0015<figref idref="DRAWINGS">FIG. 5B</figref> is an illustration of the vented brake rotor of <figref idref="DRAWINGS">FIG. 5A</figref> showing the brake rotor from a perspective wherein the rotor hat or hub portion is more easily visible.

0016<figref idref="DRAWINGS">FIG. 5C</figref> is a sectional view of a vented brake rotor according to one exemplary embodiment of the invention.

0017<figref idref="DRAWINGS">FIG. 6A</figref> is a perspective view of a vented brake rotor including an insert having a layer including graphite thereon embedded in the outboard rotor cheek according to one exemplary embodiment of the invention.

0018<figref idref="DRAWINGS">FIG. 6B</figref> is a sectional view of the vented brake rotor of <figref idref="DRAWINGS">FIG. 6A</figref>.

0019<figref idref="DRAWINGS">FIG. 6C</figref> is a perspective view of a vented brake rotor including an insert having a layer of graphite thereon embedded in the inboard rotor cheek.

0020<figref idref="DRAWINGS">FIG. 7</figref> illustrates a motor including a motor housing and an inlay and a layer including graphite interposed between the inlay and the housing according to one exemplary embodiment of the invention.

0021<figref idref="DRAWINGS">FIG. 8</figref> illustrates a vehicle transmission including a transmission housing and an insert embedded in a wall of the housing and a layer including graphite interposed between the insert and the housing, according to one embodiment, and an inlay having a layer including graphite interposed between the housing and the inlay according to another exemplary embodiment of the invention.

0022<figref idref="DRAWINGS">FIG. 9</figref> illustrates a combustion engine exhaust gas manifold including an insert or inlays with a layer including graphite interposed between a wall of the manifold and the insert or inlay.

0023<figref idref="DRAWINGS">FIG. 10</figref> illustrates a combustion engine cylinder including an insert or inlay with a layer of graphite interposed between the insert or inlay and a wall of the cylinder head.

0024<figref idref="DRAWINGS">FIG. 11</figref> illustrates a differential case including an insert or inlay and a layer of graphite interposed between a wall of the case and the insert or inlay according to one exemplary embodiment of the invention.

0025<figref idref="DRAWINGS">FIG. 12</figref> illustrates an engine block including an inlay or insert and a layer of graphite interposed between the inlay or inserts and a wall of the cylinder block according to one exemplary embodiment.

0026<figref idref="DRAWINGS">FIG. 13</figref> illustrates a rear end housing for a rear wheel drive vehicle including an insert or inlay and a layer of graphite interposed between the insert or inlay in a wall of the housing according to one exemplary embodiment of the invention.

0027<figref idref="DRAWINGS">FIG. 14</figref> is a sectional view of a golf club including a body portion and an insert, and a layer of graphite interposed between the insert and the body portion according to one exemplary embodiment of the invention.

0028<figref idref="DRAWINGS">FIG. 15</figref> illustrates a baseball bat including an insert in a wall of the baseball bat and a layer including graphite interposed between the insert and the wall of the bat according to one exemplary embodiment of the invention.

0029<figref idref="DRAWINGS">FIG. 16</figref> illustrates a shaft including a core insert in a layer of graphite thereon and a cast around body portion according to one exemplary embodiment of the invention.

0030<figref idref="DRAWINGS">FIG. 17</figref> illustrates a shaft including a substrate having an inner cylindrical wall and a layer including graphite thereon, and a cast core received in the center of the substrate according to one exemplary embodiment.

0031<figref idref="DRAWINGS">FIG. 18</figref> illustrates a bearing including a cylindrical insert and a layer including graphite thereon surrounded by inner and outer concentric body portions according to one exemplary embodiment.

0032<figref idref="DRAWINGS">FIG. 19</figref> illustrates a bearing including three lobe inserts and a layer including graphite thereon surrounded by a body portion according to one exemplary embodiment of the invention.

0033<figref idref="DRAWINGS">FIG. 20</figref> illustrates a bearing having five lobe inserts each having a layer including graphite thereon surrounded by a body portion according to one exemplary embodiment of the invention.

0034<figref idref="DRAWINGS">FIG. 21</figref> illustrates a method for testing and measuring sound damping of a brake rotor.

0035<figref idref="DRAWINGS">FIG. 22</figref> illustrates sound damping results of tests conducted on three different brake rotors, wherein the first brake rotor included no insert, the second brake rotor included an insert with a ceramic coating thereon, and the third brake rotor included an insert with a layer including graphite thereon.

0036<figref idref="DRAWINGS">FIG. 23</figref> is a graph illustrating the effectiveness of modal damping ratio reduction with coatings for 7,0 and 8,0 modes for brake rotors including no insert, an insert with a ceramic coating, and an insert with a layer including graphite thereon.

0037<figref idref="DRAWINGS">FIG. 24</figref> is a graph illustrating the mode frequency reduction ratio for a brake rotor including an insert with a ceramic coating thereon, and a brake rotor including an insert having a layer including graphite thereon.

0038<figref idref="DRAWINGS">FIG. 25</figref> illustrates the SPL dB reduction ratio for a brake rotor including an insert having a ceramic coating thereon, and a brake rotor including an insert having a layer including graphite thereon.

0039<figref idref="DRAWINGS">FIG. 26</figref> is a graph illustrating the octave band response for a brake rotor including an insert having a ceramic coating thereon, and a brake rotor including an insert having a layer including graphite thereon.

0040<figref idref="DRAWINGS">FIG. 27</figref> is a graph illustrating the modal damping ratio for brake rotors including no insert, an insert with a ceramic coating thereon, and an insert having a layer including graphite thereon and showing that an insert including a layer including graphite has both viscous and frictional damping.

0041<figref idref="DRAWINGS">FIG. 28</figref> illustrated a brake rotor insert having an annular body portion with a layer including graphite over at least a portion thereof and tabs extending from the annular body portion.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

0042The following description of the embodiment(s) is merely exemplary (illustrative) in nature and is in no way intended to limit the invention, its application, or uses.

0043Referring now to <figref idref="DRAWINGS">FIG. 2A</figref>, one exemplary embodiment of the invention includes a product <b>10</b> which may include a body portion <b>16</b> and a damping insert <b>18</b>. The damping insert <b>18</b> may include a first or upper face <b>20</b> and an opposite second or lower face <b>22</b>, the damping substrate may also include a first side <b>24</b> and an opposite second side <b>26</b>. A layer <b>28</b> including particles, such as but not limited to graphite, may be provided over at least a portion of at least one of the first face <b>20</b>, second face <b>22</b>, first side <b>24</b> or second side <b>26</b>. As shown in <figref idref="DRAWINGS">FIG. 2A</figref>, the damping substrate <b>18</b> may be in the form of an insert and the body portion <b>16</b> of the rotor cheek or product <b>10</b> may be provided around the first face <b>20</b>, second face <b>22</b>, first side <b>24</b> and second side <b>26</b>. However, the body portion <b>16</b> does not need to completely surround the damping substrate <b>18</b> and may be provided over, under or adjacent to least one of the first face <b>20</b>, second face <b>22</b>, first side <b>24</b> or second side <b>26</b>. In the embodiment shown in <figref idref="DRAWINGS">FIG. 2A</figref>, the body portion <b>16</b> includes a first inner face <b>30</b> generally facing the first face <b>20</b> of the damping insert <b>18</b>. The body portion <b>16</b> may also provide a second inner face <b>32</b> generally facing the second face <b>20</b> of the damping substrate <b>18</b>. The body portion <b>16</b> may also include a first outer face <b>36</b> and an opposite second outer face <b>38</b>. Although the damping substrate <b>18</b> is shown as an insert embedded in the body portion <b>16</b>, the body portion <b>16</b> may be provided over, under, or adjacent one or more of the first face <b>20</b>, second face <b>22</b>, first side <b>24</b> or second side <b>26</b>. For example, the damping insert <b>18</b> may be provided as an inlay in one of a first outer face <b>36</b> of the body portion <b>16</b> or opposite second outer face <b>38</b> of the body portion <b>16</b>. In yet another embodiment, the damping insert may be provided on and/or carried by the first outer face <b>36</b> or second outer face <b>38</b> of the body portion <b>16</b>. When the damping insert <b>18</b> is constructed as an inlay or a substrate overlying the first outer face <b>36</b> or second outer face <b>38</b>, tangs, tabs, post or other locking features may be utilized in the body portion <b>16</b> and/or damping substrate <b>18</b> to hold the damping substrate in position, if desired. The product <b>10</b> may be constructed and arranged so that at least one of the damping insert <b>18</b>, layer <b>28</b> or particles contained in the layer <b>28</b> may move relative to the body portion <b>18</b> so that vibration of the body portion may be damped by frictional movement of the layer <b>28</b> against the body portion <b>16</b> or insert <b>18</b>, or the movement of particles in the layer against each other or by frictional movement of the insert <b>18</b> against the body portion <b>16</b>. In other embodiments, the layer <b>28</b> is provided so that viscous energy dissipates the vibrations of the body portion <b>16</b>. <figref idref="DRAWINGS">FIG. 2B</figref> is an enlarged view of a portion of <figref idref="DRAWINGS">FIG. 2A</figref>.

0044The particles in the layer <b>28</b> may be graphite of any of a variety of types including but not limited to, flake, fiber or powder particles in natural or synthetic form.

0045Referring now to <figref idref="DRAWINGS">FIG. 3</figref>, in one exemplary embodiment, the product <b>10</b> may be a disc brake rotor including a single rotor cheek <b>40</b> connected to a rotor hat or hub <b>46</b>. A damping substrate <b>18</b> may include a layer <b>28</b> including graphite on or over at least a portion of a damping substrate <b>18</b>. The damping substrate <b>18</b> with the layer <b>28</b> may be provided as an insert, inlay or may be carried by the rotor cheek <b>40</b>. The rotor cheek <b>40</b> may include a first outer surface <b>42</b> and an opposite second outer surface <b>44</b> which may be engaged by brake pads to stop a vehicle. The insert <b>18</b> may take on a variety of configurations, and may include a continuous annular body portion <b>212</b>. Tabs <b>218</b> may extend radially outward from an outer peripheral edge <b>16</b> or radially inward from an inner peripheral edge <b>14</b> of the annular body portion <b>212</b>. The annular body portion <b>212</b> may include one or more annular ridges <b>220</b> or radially ridges <b>222</b>, if desired. The layer including graphite <b>28</b> may be provided over a portion or all of the annular body portion <b>212</b>. No coating or a coating that enhances the wetting of the tabs <b>218</b> may be provided on or at least a portion of the tabs <b>218</b>, if desired. Alternatively, a plurality of spaced apart damping substrates <b>18</b> may be provided around the circumference of the first rotor cheek <b>40</b>.

0046Referring now to <figref idref="DRAWINGS">FIG. 4</figref>, in another exemplary embodiment, first and second spaced apart damping substrates <b>18</b> may be provided in the single rotor cheek <b>40</b>.

0047Referring now to <figref idref="DRAWINGS">FIGS. 5A-B</figref>, in another exemplary embodiment, the product <b>10</b> may be a vented brake rotor including a first rotor cheek <b>40</b> and a second rotor cheek <b>48</b> may be provided and spaced apart by a plurality of vanes <b>50</b> extending therebetween. First and second damping substrates <b>18</b> with a layer <b>28</b> including graphite thereon may respectively be provided in the first rotor cheek <b>40</b> and second rotor cheek <b>48</b>.

0048Referring now to <figref idref="DRAWINGS">FIGS. 6A-C</figref>, in other exemplary embodiments, the product <b>10</b> may include a vented brake rotor including a first rotor cheek <b>40</b> and a second rotor cheek <b>48</b> in spaced apart relationship with a plurality of vanes <b>50</b> extending therebetween. A damping substrate <b>18</b> with a layer <b>28</b> including graphite may be provided in the first (outboard) rotor cheek <b>40</b> but not in the second (inboard) rotor cheek <b>48</b>. Alternatively, the insert <b>18</b> including a layer <b>28</b> including graphite may be provided only in the inboard rotor cheek <b>48</b> and not in the outboard rotor cheek <b>40</b> as shown in <figref idref="DRAWINGS">FIG. 6C</figref>.

0049Referring now to <figref idref="DRAWINGS">FIG. 7</figref>, in another exemplary embodiment, the product <b>10</b> may be a motor including a housing having a body portion <b>16</b> and an insert <b>18</b> with a layer <b>28</b> including graphite may be provided as an inlay or an insert in the body portion <b>16</b>.

0050Referring now to <figref idref="DRAWINGS">FIG. 8</figref>, in another exemplary embodiment of the invention, the product <b>10</b> may be a transmission housing including a damping insert <b>18</b> with a layer <b>28</b> including graphite over the same may be provided as an insert or inlay in a wall of the body portion <b>16</b> of the transmission housing.

0051Referring now to <figref idref="DRAWINGS">FIG. 9</figref>, in another exemplary embodiment of the invention, the product <b>10</b> may be a combustion exhaust gas manifold including a damping substrate <b>18</b> having a layer <b>28</b> including graphite may be provided in a wall of the body portion <b>16</b> of the combustion exhaust gas manifold.

0052Referring now to <figref idref="DRAWINGS">FIG. 10</figref>, in another exemplary embodiment of the invention, the product <b>10</b> may be a combustion engine cylinder head including a damping substrate <b>18</b> including a layer <b>28</b> including graphite may be provided as an insert or inlay in a wall of the body portion <b>16</b> of the cylinder head.

0053Referring now to <figref idref="DRAWINGS">FIG. 11</figref>, in another exemplary embodiment of the invention, the product <b>10</b> may be a differential case including a damping substrate <b>18</b> including a layer <b>28</b> including graphite may be provided as an insert or inlay in a wall of the body portion <b>16</b> of the differential case.

0054Referring now to <figref idref="DRAWINGS">FIG. 12</figref>, in another exemplary embodiment of the invention, the product <b>10</b> may be an engine block including a damping substrate <b>18</b> including a layer <b>28</b> including graphite may be provided as an insert or inlay in a wall of the body portion <b>16</b> of the engine block.

0055Referring now to <figref idref="DRAWINGS">FIG. 13</figref>, in another exemplary embodiment of the invention, the product <b>10</b> may be a rear end housing for a rear wheel drive vehicle including an insert <b>18</b> having a layer <b>28</b> including graphite thereon as an insert or inlay in a wall of the body portion <b>16</b> of the rear end housing.

0056Referring now to <figref idref="DRAWINGS">FIG. 14</figref>, in another exemplary embodiment of the invention, the product <b>10</b> may be a golf club iron having a head including a body portion <b>16</b> and a damping insert <b>18</b> including a layer <b>28</b> including graphite thereon as an insert or inlay in the body portion <b>16</b>.

0057Referring now to <figref idref="DRAWINGS">FIG. 15</figref>, in another exemplary embodiment of the invention, the product <b>10</b> may be a baseball bat including an insert <b>18</b> having a layer <b>28</b> including graphite may be provided in a wall of the body portion <b>16</b> of the baseball bat.

0058Referring now to <figref idref="DRAWINGS">FIG. 27</figref>, is a chart of the modal damping ratio versus mode frequency for brake rotors including no insert (<b>62</b>), a brake rotor including an insert including a ceramic coating thereon (<b>64</b>), and a brake rotor including an insert having a layer including graphite thereon (<b>66</b>).

0059Referring now to <figref idref="DRAWINGS">FIG. 17</figref>, in another exemplary embodiment of the invention, the product <b>10</b> may be a shaft having a central metal core as a body portion <b>16</b> and a damping substrate <b>18</b> having a layer <b>28</b> including graphite over an inner cylindrical surface thereof adjacent the central metal core <b>16</b>.

0060Referring now to <figref idref="DRAWINGS">FIG. 18</figref>, in another exemplary embodiment of the invention, the product <b>10</b> may be a bearing including a cylindrical damping substrate <b>18</b> as an insert embedded in a cylindrical body portion <b>16</b>. The bearing <b>10</b> may include a central bore <b>58</b> extending therethrough to receive a shaft therein. A shaft rotating in the bearing <b>10</b> may have a destructive residence frequency which could result in damage to the product in which the bearing <b>10</b> is located. The insert <b>18</b> with layer <b>28</b> including graphite provides a frictional damping means to dissipate undesirable vibration for oscillation of the shaft.

0061Referring now to <figref idref="DRAWINGS">FIGS. 19-20</figref>, other exemplary embodiments include bearings including three and five lobe inserts <b>18</b> having a layer <b>28</b> including graphite embedded in a cylindrical body portion <b>16</b> having a central bore <b>58</b> formed therethrough for receiving a shaft.

0062The insert <b>18</b> and layer <b>28</b> including graphite may be utilized in a variety of other applications including, but not limited to, hand tools, machines, manufacturing or construction equipment.

0063<figref idref="DRAWINGS">FIG. 21</figref> illustrates a test setup to measure damping of a brake rotor <b>10</b>, which as illustrated in <figref idref="DRAWINGS">FIG. 21</figref>, is a vented brake rotor including an insert <b>18</b> in the outboard rotor cheek only. A microphone or other measuring device <b>60</b> is provided to pick up vibrations or sounds associated with vibration of the brake rotor <b>10</b>. An impact hammer force illustrated by line F is applied to the brake rotor and the sound measured by the microphone <b>60</b>. Tests were performed on brake rotors including no insert in the rotor cheek, an insert including a ceramic coating thereon, and an insert including a layer including graphite thereon.

0064<figref idref="DRAWINGS">FIG. 22</figref> is a graph illustrating the SPL response due to impact force on a vented brake rotor including an insert where appropriate in the inboard rotor cheek. Line <b>62</b> represents the response for a rotor with no insert, line <b>64</b> represents the response for a rotor including ceramic coating such as ladekote on the insert, and line <b>66</b> represents the response for an insert including a layer including graphite thereon.

0065<figref idref="DRAWINGS">FIG. 23</figref> is a graph illustrating the SPL (dB) versus frequency (Hz) for brake rotors without an insert (<b>62</b>), a brake rotor including an insert including a ceramic coating thereon (<b>64</b>) and a brake rotor including an insert having a layer including graphite thereon (<b>66</b>). It should be noted that for the mode (7,0) and mode (8,0), the insert with the graphite provided greater damping.

0066<figref idref="DRAWINGS">FIG. 24</figref> is a graph of the mode frequency reduction ratio for brake rotors including a ceramic coating on the insert (<b>64</b>) and a brake rotor including a layer including graphite on the insert (<b>66</b>).

0067<figref idref="DRAWINGS">FIG. 25</figref> is a graph illustrating the SPL dB reduction ratio for a rotor including a ceramic coating on an insert (<b>64</b>) and a rotor including a layer including graphite on the insert (<b>66</b>). It should be noted in <figref idref="DRAWINGS">FIG. 24</figref> that graphite shows slightly more frequency reduction in the low frequency modes. It should be noted that in <figref idref="DRAWINGS">FIG. 25</figref>, graphite shows overall more SPL reduction for all modes except mode (8,0).

0068<figref idref="DRAWINGS">FIG. 26</figref> is a chart illustrating the summary of octave band responses for brake rotors including an insert having a ceramic coating thereon (<b>64</b>) and a brake rotor including an insert having a layer including graphite thereon (<b>66</b>). As shown in <figref idref="DRAWINGS">FIG. 26</figref>, graphite shows overall more octave band reduction for high frequency bands except for 8K band.

0069Again, <figref idref="DRAWINGS">FIG. 27</figref> is a chart of the modal damping ratio versus mode frequency for brake rotors including no insert (<b>62</b>), a brake rotor including an insert including a ceramic coating thereon (<b>64</b>), and a brake rotor including an insert having a layer including graphite thereon (<b>66</b>). As will be appreciated from <figref idref="DRAWINGS">FIG. 27</figref>, the use of a layer including graphite-based material possesses both viscous and frictional damping, wherein the ceramic coated insert rotor showed little frictional damping at certain modes (8 circumferential mode).

0070According to one exemplary embodiment of the invention, a layer <b>28</b> may be provided on the insert <b>18</b> by a variety of methods. For example, the graphite material may be any form of graphite or graphite oxide blends with an organic or inorganic binder, mixed with clay, with water, petroleum solvent or alcohol and applied to the insert <b>18</b>. In other embodiments, the graphite may be simply pressed onto the insert <b>18</b>. Yet, in another embodiment, the graphite may be treated with functional groups to enhance the loose bonding of the particles to each other. The layer <b>28</b> including graphite may be deposited on the insert to a thickness sufficient so that the graphite does not cause molten metal to bond to the insert <b>18</b>. In one exemplary embodiment, the layer <b>28</b> including graphite is based on the insert <b>18</b>, for example, the insert <b>18</b> with a layer <b>28</b> may be baked at a temperature ranging from 50° C. to 500° C. for a period of about 5 to about 35 minutes or for at a temperature range and time sufficient to prevent molten cast metal cast around the insert <b>18</b> from removing the layer <b>28</b>.

0071Suitable binders may include, but are not limited to, epoxy resins, phenolic acid binding agents, calcium aluminates, sodium silicates, wood flower, or clays. In other embodiments, the layer <b>28</b> may include at least one of clay, aluminum oxide, silicon dioxide, silicon carbide, silicon nitride, cordierite, magnesium-iron (aluminum silicate), mullite (aluminum silicate), zirconia (zirconium oxide) or phyllosilicate in addition to graphite. In other embodiments, the layer <b>28</b> may include a fiber such as ceramic or mineral fibers. In one exemplary embodiment, the layer <b>28</b> when applied to the insert may include a solids portion, including the graphite ranging from about 5 to about 100 weight percent and a liquid portion, including any binder, ranging from about 95 to about 0 weight percent; from about 60 to about 20 weight percent, or temperature or weight percent ranges therebetween. In another embodiment the graphite may be mixed with refractory type materials that are chemically and physically stable at high temperatures, for example including but not limited to oxides of aluminium (alumina), silicon (silica), magnesium (magnesia), calcium (lime), firclays, zirconia and/or silicaon carbide.

0072The exact thickness of the layer <b>28</b> may vary. Examples of suitable thicknesses may range from about 1-650, 10-400, 30-300, 30-40, 40-100, 100-20, 120-200, 200-300, 300-550, 350-450, 300-600 μm, or variations of those ranges.

0073The damping substrate <b>18</b> may be made from a variety of materials, including, but not limited to, steel, aluminum, ceramic, polymeric, or any other suitable material for damping. If the body portion <b>16</b> is a metal cast around the damping substrate <b>18</b>, preferably the damping substrate <b>18</b> has a melting point higher than the cast material. For example, if the body portion <b>16</b> includes cast iron, the damping substrate <b>18</b> may have melting temperatures above 1100° F., above 2400° F., or above 2700° F.

0074Embodiments for the product <b>10</b> is made using a process wherein the damping substrate <b>18</b> and/or the graphite material is not subject to relatively high temperatures associated with molten metals, the damping substrate <b>18</b> may be made from a variety of other materials including, but not limited to, non-refractory polymeric materials, ceramics, composites, wood or other materials suitable for frictional damping.

0075In one illustrative embodiment, the damping substrate <b>18</b> may have a minimum average thickness of 0.2 mm and/or a minimum width of 0.1 mm and/or a minimum length of 0.1 mm. In another exemplary embodiment, the damping substrate <b>18</b> may have a minimum average thickness of 0.2 mm and/or a minimum width of 2 mm and/or a minimum length of 5 mm. In other exemplary embodiments, the damping substrate <b>18</b> may have a thickness ranging from about 0.120 mm, 0.1-6 mm or 0.1-2.5 mm or ranges therebetween.

0076It is believed that the use of an insert with a baked on coating of sufficient thickness as set forth above, wherein the coating including particles consisting essentially of graphite without refractory materials, and with or without a binder provides improved damping by impacting high and low frequencies vibration modes.

0077The above description of embodiments of the invention is merely exemplary in nature and, thus, variations thereof are not to be regarded as a departure from the spirit and scope of the invention.